#!/usr/bin/python
# -*- coding=utf-8 -*-

import os, sys

def run_shell(command, *args):
	"method used to run the shell command passed to it"
	if len(args)>0:
		command=command%(args)

	os.system(command)

def alias_config(**alias_dict):
	"method used to config shell alias with a dict data object"
	alias_config_pattern="alias %s=%s"
	for key in alias_dict:
		command=alias_config_pattern%(key,item[key])
		run_shell(command)

def env_var_exists(name):
	"test if a evironment variable exists"
	if name in os.environ:
		return True
	return False

def get_enr_var(name):
    
    if env_var_exists(name):
        return os.environ

def file_exists(filename):
	return os.path.

if __name__ =="__main__":
	run_shell("ls")
